This invention relates to a control system for controlling the working depth of a tractor-coupled implement as a function of various sensed and operator-controlled parameters.
A hitch control system for controlling implement working depth as a function of various sensed vehicle and implement operating parameters and operator-generated command signals is described in U.S. application, Ser. No. 360,748, filed Mar. 22, 1982. The control system described therein has a control lever and transducer for generating a position command signal, as well as a rotatable control knob and potentiometer for generating draft or load command signals representing desired hitch positions and desired draft forces. Other hitch control systems, such as described in U.S. Pat. Nos. 4,300,638 and 3,860,074, require separate operator-controlled position and draft force control levers or knobs for the production of position and draft force error signals. It would be desirable, in a hitch control system which is responsive to a position error and load error, to reduce the complexity of these operator controls by eliminating the load control knob or lever.